Clamp



Oct. v23, 1945.4 F. c. WALLACE 2,387,3'7l

f l CLAMP f v -v Filed Nov.h 5, 1944 --/7- Z5' i @SiN l su@ @Uff "g gyzf//l7/ INVENTOR.;

El ank 5,. L/a/ Patented Oct. 23, (1945 l CLAMP` Frank c. Wallace, Norm ntnywoa, calif., u

assignor to Herman Hl Helbush, Los Angeles,

Calif..

, `Application l l'llllyinvention` has to do ,with clamps, relating more` particularly to sheet metal clamps.

` Conventional sheet metal :clamps have a cylinwith. an opening therethrough and in which housing are reciprocallyf mounteda pair of retaining orHclainping` `pins which are urged into clamping position by a compression spring, there being a `flat spreader bar interposed between the retain` ing pins.

Such clampsiare relatively costly to manufacture if they are to possess any considerable strength since the body must be formed by ascrew machine. If drawn by a stamping the body` isnecessarily too thin and shell-like.

Moreover, in some clamping jobs theclamping pressure required is greater `than may `be practicably obtained from use` of a spring pressure compressive stress on the body and to withstand this stress the body side walls `must possess considerable `section and strength. Also', the time and eiort required to assemble `such a clamp are such as` to materially add` to their cost.

f `It is, therefore, among the objects of my invention to provide a sheet metal clamp. the housing or `body of which is of aiconstruction which may be economically formed of stampings Without being. `drawniand. vwhich `possesses the requisite section and strength to render it highly durable and capable of withstanding the longitudinal compressive stresses incident to utilizing a screw type of clamping member.

Another object of the invention is .to provide a clamp of i a novel construction which treinen dously facilitates and reduces the `expense of as- Sembly. i

Another object is the provision of such a clamp of novel and efficient means for securing the re-` taining element in` assembly.. 1

My invention possesses stili `further objects and. features of novelty `and advantage which will be readily understood by those working in the art from a consideration ofthe following detailed description of one embodiment thereof which I have chosen for explanatory purposes, it being understood, of course, that within the scope of the appended claims, the invention is capable of being lembodiedin other and modified physical forms. i Y

purposes of the following `description,l

` drical body or housing presenting an end wall I November 3, 1944, serial No. 561.735

s anims. (ci. 85-5) shall refer to the accompanying drawing',

which.: c v

` Fig.. lis a. medial longitudinal section, some parts being' shown in elevation;

, 2 is atop plan View;

is .asection on line 3-f-3 of Fig/1.; Fig. `4 is a section on line `4---4 of Fig.2; Fig. 5 is a perspective of a portion of the body;` Fig. 6' is a perspective of another portion .ot the body; 1 Fig.. 7 is aside View of the spreader bar; and Fig.. 8 is a.. fragmentary section of the retaining element. i i

.ReferringA now'to the drawingr B generallydenotes `the body or housing and. R. the retaining element. i

The body Bis comprised of two metal. stamp-` ings 5 and lshown in perspective in Figsr 5 and 6, respectively, which are `first formed `as -flat blanks and then stamped .in-to the shapes shown.

The body elementsi, which I shall term the casing,` has side wallsA 8,. -9, lll and an end Wall H1 presenting an opening I2. Side walls Si: and l0 have slots l5 intheir top edges and slots t6 in their inner*l end edges; 'A pair of opposed ears ll are formed integral withthe sides A9 and IU to provide manual gripping members.

Then body element 6, which lI vshall term the ,V cover plate, consists of a plate 2.0 havingsi'de lugs 2'1` and right angled: end portions Z2, 23. The end portion 22 presents a recess 22a and endl lugs 252i).- End portion 23 presents an opening 23a and laterally projecting lugs 2'4, 25.

When assembled, the cover plate ts into thel open side portion of the casing between the two side walls 9, l0, the lugs 2l `fitting into the slots F51, thev lugs 24 fitting in the slots f6 and the lugs 25 tting against the inner end edge of the casing. Recess 22a Aand opening 23a are in axial alinernent with the opening |52 in the casing end wall, while the outer ends of lugs 22h bear against the inner; 4surface -of the casing end wall H.

The: retaining element R comprises a threaded plunger 30 which projects from the inner end outwardly oi the casing through recess 22a and opening I2. A flat T-shaped spreader bar 49 having a central leg portion 4I and a cross arm portion 42 is interposed between the retaining pins, the center leg 4I extending outwardly through opening I2 between the retaining pins a distance at least as great as the thickness of any work sheets to be clamped. The cross arm portion of thespreader is held against longitudinal movement by fitting betweenthe end wall,

II and the end portion 22 of the cover plate. The lugs 22h engage behind the cross arm 42 of the spreader to prevent the cover plate 6 from escaping from the casing. Each of the retain--A wing nut 32 andthe end portion 23 of the cover plate.

To assemble the device the plunger 30, :collar 35 and the retaining pins are first assembled and the spreader bar 4I)v placed between the retaining pins with its cross arm 42against the adjacent end of the plunger, so that the outer end of the central leg `4I of thespreader is spaced inwardly from the outer ends 43 of the retaining pins. With the parts thus assembled, the outer ends 43 of the retaining pins are inserted through the opening I2 and the spreader bar is then moved longitudinally between the pins until its central leg projects outwardly through opening VI2 and the cross arm portion rests against the inner surface of end wall II. Nextthe inner end of the plunger 30 is inserted through opening, 23a in the cover plate and the opposite end of the cover plateis inserted between the sidewalls 9, I0 so that the retaining pins extend through the recess 22a, the lugs 22h being insertedbehind the cross arm portion of the spreader bar. plate is then secured in position by snapping the lugs 2| in slots I5 and the lugs 24 in-slots1l6.` Then after applying the lock washer and win nut the device is ready for use. 'Y n Operation of the device is as follows: With the outer ends of the retaining pins protractedfrom the body far enough to remove the Vouter end lof the central leg ofthe spreader bar inwardly from between the pin ends 43 (Fig. l) theretaining pins are inserted through the vregisteringholes 50 in the work sheets S which it is desired t0; clamp together, the end wall I I of the body bearing against the innermost sheet. The wing nut 32 is then rotated and inasmuch as the plunger is held against rotation by virtue of the hexagonal cross section of the collar 35, the retainingpins are retracted until their shoulders 44 engage the outermost work sheet SA, thus clamping the- Work sheets between the shoulders1'44 and theV end wall II. Inasmuch as the end wallII bears against the outer end edges of the sides 9 and I0 andthe lugs 24, 25 of the cover plate bear'against the opposite end edge of the casing, it will vbe seen that considerable clamping pressure may be applied by the nut 32. As the retaining pinsare retracted into clamping position their outer ends 43 are spread apart by the longitudinally stationary spreader bar. To remove the clamp `from the work the nut 32 is unscrewed so that the' plunger may be pushed inwardly ofl the body to"` protract the retaining pins again to the position of Fig. 1, in which position they may be4 withdrawn from the work. When the device is not in use the combined diameter of therretaining' pins The cover= and spreader is such that the shoulders 44 will engage the outer surface of the body end wall and prevent the outer ends of the retaining pins from passing inwardly through the opening I2.

I claim:

1. In a sheet metal clamp, a casing having three sides and a bottom end Wall presenting an opening therethrough,` a platemounted on and forming the fourth side'of the casing, said plate having a right angled outer end portion fitting over and providing a closure for the open end of the casingand having an opening coaxial "with the mst-mentioned opening, a retaining member reciprocally mounted in the casing and projecting at its respective ends through said openings, and means for releasably retaining the plate on the casing 2. In a sheet metal clamp, a casing having4 projecting at its respective ends through ,said

openings, one end of the retaining member being comprised of a pair of laterally flexible worin` engaging pins, a spreader bar mounted in the easing between the pins, and means for retaining the inner end of the plate against lateralV movement relative to the casing, including a lug on the inner end of the plate engaging the spreader bar. f

3. In a sheet metal clamp,y a casing having three sides and a bottom end wall presenting an opening therethrough, two of A,said sides presenting slots in their side and top end edges, a plate mounted on and forming 'the fourth side? of the casing, said plate having side lugs engage-' able in the slots in the side edges of the sides and having a right angled end portion providing" a closure for the top end of the casing and pre! senting lugs engageable in the end slots Vin the casing sides, said right angled end portion having an opening coaxial withtl'ie rst-mentioned opening, and a retaining memberl reciprocally mounted in the casing and projecting at its re-l spectivey ends through said respective openings.

4. VIn a sheet metal clamp, a casing having` three sides and a bottom end wall presenting an opening therethrough, two of said sides presenting slots in' their side and top end edges, aV plate mounted on and forming the fourth side of the casing, said plate having side lugs engageable inv the slots in the side edges of theA sides and hav-l ing a right angled endy portion providing'a closure for the top end of the casing and present-` ing lugs engageable in the end slots in the cas/- ing sides, said right angled end portion having' an opening coaxial with the first-mentioned opening, a retaining member mounted in the casing and projecting at its respective ends through said respective openings,r

said retaining member having a threaded inner end, and means for moving the retaining mem-Y ber in one direction relative to the casing, comprising a nut threadedly engaging the inner end"` of the retaining member.

5. In a sheet metal clamp, a casing havingv three sides and a bottom end wall presenting an opening therethrough, two of said sides presentmounted on and forming the fourth side of the reciprocally` casing, said platehaving side lugs engageable in the slots in the side edges of the sides and having a right angled end portion providing a closure for the top end of the casing and presenting sides, said right angled end portion having an opening coaxial With the first-mentioned opening, i a `retaining member reciprocally mounted in the casing and projecting at its respective ends through said respective openings, said retaining member having a threaded inner end, and means for moving the retaining member in one direction relative to the casing, comprising a nut threadedly engaging the inner end of the retaining member, said nut being engageable against the right angled end portion of the plate.

6. The clamp of claim 4 in which the retaining member has a portion of angular cross-section engageable with the sides of the casing to prevent rotation of the retaining member relative to the casing.

7. In a sheet metal clamp, a casing having three sides and a bottom end Wall presenting an opening therethrough, a plate mounted on and forming the fourth side of the casing, said plate having a right angled outer end portion tting over and providing a closure for the open end of the casing and having an opening coaxial with the first-mentioned opening, a retaining member reciprocally mounted in the casing and consisting of an externally threaded inner end portion projecting through the opening in theV 8. The clamp of claim 7 inwhch the plate has an inner end portion engaging that portion of the spreader bar disposed in the casing to prevent longitudinal movement of the spreader bar in one direction relative to the pins.

FRANK C. WALLACE. 

